Method of making cup brushes



March 7, 1933; R. G. MERTi-:s

METHOD OFMAKING CUP BRUSHES Filed April 13, 1931 illilll will.

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Patented Mar. 7, 1933 UNITED STATES PATENT OFFICE ROBERT G. MERTES, 0F CATONSVILLE, MARYLAND, ASSIGNOR THE PITTSBURGH PLATE GLASS COMPANY, 0F PITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA METHOD OF MAKING CUP BRUSHES Application led April 13,

This invention relates to a method of making a cup brush, and more particularly to the method of assembling the various elements of a cup brush into a unitary structure.

It is among the objects of this. invention to provide a `method of assembling ay cup brush whereby the bristles will be anchored at a point intermediate their respective, ends to thereby strengthen and avoid the partaking of torsion on the part of the individual bristles. It is still another object of this 1nvention to provide a method of forming a cup brush wherein the finished product may be easily constructed at a comparatively low cost, and in addition may be quickly assembled into a unitary structure.

This invention contemplates the metliod of assembling a cup brush wherein a point or line of greatest pressure is created across the bristle body between the periphery of the base plate and the cupped plate. More particularly the cup brush is adapted to embody one or more brush sections wherein the bristle body is looped around a strand of wire adapted to take the form of a. ring. Two plates having inwardly pro]ecting lugs are each individually secured to the bristle body on opposite sides through the medium of the lugs which extend through and engage the exposed portion of the bristle body. These lugs serve the further purpose of preventing the rotation of the bristles relative to the side plates. The brush sections so formed are then mounted on a sleeve between two plates of dierent diameters and secured together. The larger plate is then cupped over the smaller to form the bristle body into a relative cup. The cupping of the larger plate is such as to produce a pressure area across the bristle body at the bend which results in the stabilizing of such bristle to render them unable to partake of any torsion:

Other objects, more or less ancillary to the foregoing, and the manner in which all the various objects are realized will appear in the following description, which, considered in conjunction with the accompanying drawing, sets forth the preferred embodiment of the invention and wherein:

Figure 1 is a front elevation of the pre- 1931. serial No. 529,731.

ferred form of brush section used in the construction of the cup brush.

Figure 2 is a vertical longitudinal section of the .assembled parts prior to the cupping operation.

Figure is a side elevation, partly in sec tion, showing how the bristles are directed at an angle to form a working face in a plane parallel to one of the side plates.

With reference to the drawing and more particularly to Figures vl and 2 there is illustrated the preferred form of brush section comprising annular side plates 1 and 2 that are mounted on the opposite sides of the bristle body 3. The bristle body 3 which preferably consists of fine wire, tampico, hair or like material is arranged radially around the periphery of the side plates, the mid-portion of such material being looped about `a strand of wire adapted to take the form of a ring 4 and disposed between the plates as shown.

The side plates 1 and 2 are preferably made up of annular blanks having central apertures 5 to permit the mounting thereof on a sleeve 6. Triangular lugs 7 are stamped out of the body of the side plates and are adapted to be turned inwardly at right angles to the plane of the plate. The Iside plates 1 and 2 are secured to the bristle body through the medium of the lugs 7 which extend through the bristle body and engage'or are turned over the opposite side of the bristle body. When both of the side plates l and 2 are secured to the bristle body the lugs 7 extend through the openings formed by the stamped out lugs on the opposing plates and are turned over the bristle body into the plane of such plate.

In making the cup brush the sleeve is first turned over or beaded at 8, and a large annular plate 9 is then placed thereon. 'Iwvo brush sections 10 and 1l constructed as hereinafter described are next placed on the sleeve, the larger section 10 being placed adjacent the plate 8. A plate 12 is then placed over the sleeve and the assembled parts are subjected to hydraulic pressure and the parts secured together by rolling the end 13 of the sleeve 6 similar to that as at 8. It is to oov be noted that the plate 12 is of no greater diameter than the side plates of the section. The brush sections are made of different diameters in order that when the plate 8 has been cupped a working surface is presented which necessitates little or no trimming, thus economizing in material.

The assembled brush as shown in Figure 2 is then subjected to a forming die and the larger plate 9 is diverged inwardly toward the smaller plate 12 thereby firmly clamping the' bristles between the periphery of the plate 12 and the inner face of the cupped portion of the plate 9. It is desirable to make the distance between the c up portion and the periphery of the plate 12 considerably less than the distance 'between the plates S and 12 adjacent the sleeve 6 to avoid any 'movement of the bristles between these plates.

In other words the point of fixation of the bristle member is transferred from the ring 4 to the pressure line between the edge of the plate 12 to the inner face of the cupped plate 9.

It will be apparent from the foregoing that a method of forming a cup brush has been disclosed which is simple in its various steps and is therefore conducive of economic construction. The cup brush so formed by this method is readily adapted to be mounted on a rotary tool of the usual type. Further, this method obviates the necessity of a, reat amount of trimming of the surface which is adapted to be presented to the work.

Although the foregoing description is necessarily of a detailed character in order to completely set forth this invention it is to be understood that the specic terminology is not intended to be restrictive or confining and it is further.` understood that various rearrangements of parts and modifications of structural detail may be resorted to without departing from the scope or spirit of the P invention as herein claimed.

I claim:

1. The method of constructing a cup brush which consists in disposing a plate upon a cylindrical sleeve, mounting a plurality of radially extending bristle bodies upon the cylindrical sleeve, one of said bristle bodies being of lesser diameter than the other of said bristle bodies, and then directing the bristles at an angle to produce a working face in a plane at right angles to the center line of the sleeve by bending and securing the plate thereover.

2.` The method of constructing a cup brush which consists in first forming a brush section by looping bristle material about a strand of wire forming a ring, clamping said looped portion between annular plates disposing a forming plate upon a sleeve, mounting the section on the sleeve, and then directing the bristle material at an angle to said 1,ooo,575

plates by deflecting the :forming plate thereover.

3. The method of constructing a cup brush which consists in disposing a plate upon a sleeve forming a brush section having radially extending bristles, mountin a plurality of said sections on the sleeve an then direct-- ing the bristle material at an angle by bending the plate thereover.

4. The method of constructing a cup brush which consists in first forming a brush section by looping bristle material about a strand of wire forming a ring, securing side plates to the looped portion of the bristle material disposing a forming plate upon a sleeve` mounting a plurality of brush sections on the sleeve and then directing the bristle material at an angle by bending the plate thereover.

5. The method of constructing a cup brush which consists in first forming a brush section by looping bristle material about a strand of wire forming a ring, securing side plates to the bristle material by lugs integrally formed with said side plates and extending through the bristle material and engaging the opposite side of said material disposing a forming plate upon a sleeve, mounting a plurality of brush sections on the sleeve and then directing the bristle material at an angle by bending the forming plate there-` over.

6. The method of constructing a cup brush which consists in first forming a brush section by looping bristle material about a strand of wire forming a ring, securing side plates to the bristle material, mounti a plurality of said sections on a sleeve tween plates of dilerent diameters, securing the sleeve, plates and brush sections together, and then directing the bristle material at an. angle to said plates by delecting the larger late toward the plate oi: less diameter.

7. The method of constructin a cup brush which consists in first formin a rush section by looping bristle material a out a strand of wire forming a ring, securing side plates to the bristle material, mounting a plurality of sections of different diameters on a sleeve between plates of dierent diameters, securing the sleeve, plates and brush sections together, and then directing the bristle material at an angle to said plates by deilecting the plate of greater diameter toward the Vother plate thereby presenting a working surface substantially parallel to the plates.

8. The method of making a cup brush which consists in disposin a forming plate upon a sleeve, mounting rush sections of diierent diameters having radially extending bristles upon the sleeve and deilecting Y' which consists of mounting disc like brushv sections of different diameters axially on a sleeve, mounting plates of different diameters on opposite sides of the mounted sections, securin the sections between the plates and then eflecting the plate of greater diameter toward the plate of lesser diameter.

10. The method of making a cu brush which consists ofassembling a brist e body, having radially extending bristles, between plates of different diameters, securing the plates together, and then deforming the outer peripheral portion. of the plate of greater diameter toward the outer edge ot the plate of lesser diameter thereby securely clamping the bristle body between the inner wall of the deected plate and the peripheral edge of the smaller plate.

In testimony whereof I hereunto .ax my 2 signature this fourth da of April, 1931.

ROBE T G. MERTES. 

